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K M Sullivan

Publications and source records attributed to K M Sullivan.

At least 235 records · Page 13Linked to original sources
PubMed1987

Influence of cation size and charge on the extrusion of a salt-dependent cruciform.

We have made a comparative study of the kinetics of cruciform extrusion by a salt-dependent (S-type) cruciform in the presence of a variety of metal ions and related species. We find that the nature of the cation present has a marked effect on the observed kinetics, and that different cations differ greatly in the efficiency with which they promote the extrusion process. We can divide the ions into four classes according to the optimal ionic concentration required for maximal extrusion rate. Group Ia cations and tetramethyl ammonium are most effective in promoting extrusion at 50 to 60 mM. Group IIa and selected transition metal ions (notably manganese) are effective over a wide range, extending down to 200 microM. Hexaminecobalt(III) and the polyamines promote extrusion at concentrations as low as 15 to 40 microM. Most remaining ions examined, including trivalent ions such as Al(III) and many transition metal ions are totally ineffective. Within the first two groups, we observe a marked correlation between the rate of cruciform extrusion promoted and ionic radius, the larger ions giving faster extrusion rates. We interpret this to indicate specific ion binding occurring in the transition state of the extrusion process. We may rationalize all the data in terms of a model for salt-dependent cruciform extrusion, in which the transition state resembles a partially extruded protocruciform. This creates an anionic "cavity" with selective ion binding properties, and its stabilization is therefore ion size-dependent.

Anions↗
PubMed1987

Marrow transplantation for acute nonlymphocytic leukemia following therapy for Hodgkin's disease.

Seven patients with acute nonlymphocytic leukemia (ANL) following therapy for Hodgkin's disease (HD) were treated with cyclophosphamide (Cy) alone or combined with 10.00 to 15.75 Gy total body irradiation (TBI) and marrow transplantation. Five patients were transplanted without an attempt at prior remission induction, one patient following failure of remission induction and one patient in first remission following successful induction. Four patients died of multiorgan failure, 15 to 70 days after transplant. Three patients died of progressive or recurrent leukemia 56, 120, and 280 days after transplant. These results illustrate the difficulty of treating patients for secondary leukemia with marrow transplantation and suggest that transplantation in the preleukemic phase should be studied.

Acute Disease↗
PubMed1987

Treatment of malignant lymphoma in 100 patients with chemotherapy, total body irradiation, and marrow transplantation.

Between July 1970 and January 1985, 100 patients with malignant lymphoma were treated with high-dose chemoradiotherapy and bone marrow transplantation. Twenty-eight of the 100 are alive and the actuarial probability of disease-free survival 5 years from transplantation is 22%. The most common reason for treatment failure was disease recurrence, with an actuarial probability of 60%. A proportional hazards regression analysis showed that the likelihood of disease-free survival was less in those patients transplanted in resistant relapse and in those previously treated with chest radiotherapy. Neither disease histology (Hodgkin's disease, high-grade lymphoma or intermediate-grade lymphoma), nor source of marrow (syngeneic, allogeneic, or autologous) significantly influenced either disease-free survival or probability of relapse. The use of high-dose chemoradiotherapy and marrow transplantation appears to offer a better chance for long-term survival than any other form of therapy for young patients with disseminated malignant lymphoma whose disease has progressed after initial combination chemotherapy. The best results with marrow transplantation were obtained in patients transplanted in early relapse or second remission who had not received prior chest radiotherapy.

Adolescent↗
PubMed1987

Risk factors for airflow obstruction in recipients of bone marrow transplants.

Obstructive lung disease is a complication of bone marrow transplantation. To identify risk factors we analyzed pulmonary function tests of 281 adult patients 1 year after marrow transplantation. The forced expiratory volume at 1 second divided by the forced vital capacity (FEV1/FVC) was used to measure airflow rates. Factors associated with a lower year-1 FEV1/FVC (%) included increased age (p less than 0.0001), male gender (p = 0.02), cigarette smoking (p = 0.01), lower FEV1/FVC before transplantation (p less than 0.0001), HLA-nonidentical grafts (p = 0.001), chronic graft-versus-host disease (p = 0.0002), and immunosuppressive therapy with methotrexate (p = 0.01). There was no significant association between the year-1 FEV1/FVC and underlying disease, dose of conditioning irradiation, or development of acute graft-versus-host disease. Linear multivariate regression analysis, after controlling for the FEV1/FVC before transplantation, shows both chronic graft-versus-host disease and administration of methotrexate independently associated with decrements in the year-1 FEV1/FVC. The combined occurrence of chronic graft-versus-host disease and methotrexate also was strongly associated with decreases in the year-1 FEV1/FVC, indicating an interaction of these risk factors.

Adult↗
PubMed1987

Prophylactic use of human leukocyte interferon after allogeneic marrow transplantation.

STUDY OBJECTIVE: To determine the efficacy of prophylactic interferon for prevention of cytomegalovirus infection and relapse of leukemia after allogeneic marrow transplantation. DESIGN: Randomized trial with intermittent interferon administration to day 80 after transplantation. SETTING: Marrow transplantation units of a cancer research center. PATIENTS: Consecutive patients with acute lymphocytic leukemia in remission at the time of transplantation. Thirty-nine patients received interferon, and 40 were control patients. INTERVENTIONS: Partially purified human leukocyte interferon given every 3 days beginning after marrow engraftment and continuing to day 80 after transplantation. After initial safety testing, the starting and minimum dose was 6 X 10(4) units/kg of body weight, with dose escalations determined by the circulating neutrophil count. Transplant conditioning and post-transplantation prophylaxis of graft-versus-host disease with methotrexate followed standard procedures. MEASUREMENTS AND MAIN RESULTS: No difference was observed in the probability or severity of cytomegalovirus infection or in the probability or severity of graft-versus-host disease. Relapse of leukemia occurred in 9 interferon recipients and 21 control patients, with a minimum follow-up of 4 years among surviving patients. The probability of relapse among all interferon recipients was 0.36 (95% confidence interval [Cl], 0.56 to 0.17) and among all control patients was 0.74 (95% Cl, 0.91 to 0.58) (p = 0.04 by log-rank test). Among patients who received transplants in first or second remission, the probability of relapse among interferon recipients was 0.19 (95% Cl, 0.37 to 0.02) compared with 0.71 (95% Cl, 0.97 to 0.51) among control patients (p = 0.008 by log-rank test). Survival rates did not differ between interferon recipients and control patients. Transient decreases in leukocyte count and anorexia and nausea occurred among interferon recipients. Six interferon recipients, all of whom had received chemoradiotherapy of the central nervous system before transplantation, developed leukoencephalopathy after transplantation. CONCLUSIONS: These data suggest that interferon given after transplantation reduces the risk for subsequent relapse of leukemia. The effect of longer administration and of administration in patients with other underlying diseases will require additional trials. No effect was observed on cytomegalovirus infection, either because interferon was not initiated until a median of 18 days after transplantation or because of a lesser effect among marrow allograft recipients.

Adolescent↗
PubMed1987

The effect of prophylactic intravenous immune globulin on the incidence of septicemia in marrow transplant recipients.

Ninety-seven patients randomized to receive (45 patients) or not to receive (52 patients) intravenous cytomegalovirus immune globulin before and after allogeneic marrow transplantation were evaluated retrospectively for the occurrence of bacterial and fungal septicemia in the first 100 days post-transplant. In a proportional hazards regression test, infection prevention regimens, immunoglobulin administration, age and occurrence of acute graft-versus-host disease were tested simultaneously for the occurrence of septicemia in the pre- and post-engraftment period. Of these factors, only patients receiving immunoglobulin had significantly fewer episodes of septicemia following engraftment with 11 (26%) patients in the globulin group having 14 episodes compared to 22 (42%) patients in the control group having 27 episodes (p = 0.039). None of the patients experienced complications with the immunoglobulin infusions. These results suggest that the administration of intravenous immunoglobulin may be a practical and effective method to decrease the incidence of septicemia following marrow transplantation.

Bone Marrow Transplantation↗
PubMed1987

Second marrow transplants in patients with aplastic anemia rejecting the first graft: use of a conditioning regimen including cyclophosphamide and antithymocyte globulin.

Sixteen (11%) of 146 consecutive patients with severe aplastic anemia prepared for engraftment with cyclophosphamide (200 mg/kg) rejected marrow grafts from their HLA-identical siblings. They were given a second marrow transplant from either the same (n = 13) or a second (n = 3) HLA-identical sibling between 23 and 743 (median 86) days after the first transplant. The preparation for the second transplant included cyclophosphamide, 50 mg/kg, on each of four successive days. Twelve hours after each of the first three doses of cyclophosphamide, antithymocyte globulin, 30 mg/kg/dose, was infused. One of the 16 patients died from infection too early after the second transplant to be evaluated, two had failure of engraftment and died with infection, one rejected the second graft and is surviving almost 5 years later with full autologous marrow recovery, and 12 had successful and sustained second grafts. Of these 12, six are surviving between 11 months and 7 3/4 years. Four of the six have no graft-v-host disease (GVHD), while two have chronic GVHD requiring treatment. Five have Karnofsky scores of 100% and one of 90%. Six of the 12 patients with sustained grafts died between 63 days and 38 months after transplantation, four with infections (related in two patients to chronic GVHD), one with acute GVHD, and one with hemorrhage. The average interval from first to second transplant was 308 days during the past five years, compared to 61 days in earlier patients. Five of seven recent patients are surviving, compared to two of nine earlier patients. In conclusion, successful second transplants after cyclophosphamide and antithymocyte globulin are possible in most patients with aplastic anemia who have rejected their first marrow grafts; however, mortality remains high, with only 40% of the patients becoming long-term survivors.

Adolescent↗
PubMed1987

Graft-versus-leukemia in man: relationship of acute and chronic graft-versus-host disease to relapse of acute leukemia following allogeneic bone marrow transplantation.

To study the effect of acute and chronic graft-versus-host disease (GVHD) on recurrent leukemia, we analysed data on patients with acute leukemia receiving allogeneic marrow transplants in Seattle between 1970 and 1986. Four hundred fifty-four patients survived in remission 150 days after HLA-identical transplant and 114 currently survive five to fifteen years after marrow grafting. At the time of transplant, 252 patients had acute nonlymphocytic leukemia in remission or relapse and 202 had acute lymphocytic leukemia in remission or relapse. According to Kaplan-Meier estimates, recurrence of leukemia following transplantation was observed in 28% of patients developing moderate to severe (grade II-IV) acute GVHD and 48% of patients with no or mild (grade O-I) acute GVHD (p = 0.0028). Relapse was observed in 34% of patients developing clinical extensive chronic GVHD and 45% of patients free of chronic GVHD (p = 0.0001). The incidence of recurrent leukemia was 28% in recipients developing both acute and chronic GVHD and 52% in patients free of both acute and chronic GVHD (p = 0.0001). These data confirm an apparent graft-versus-leukemia effect in patients developing GVHD after allogeneic marrow grafting. Current studies are aimed at determining the influence of such apparent adoptive immunotherapy within the different categories of leukemia and methods to manipulate and augment the clinical benefit of this observation.

Acute Disease↗
PubMed1987

Graft versus leukemia effect in man: the relapse rate of acute leukemia is lower after allogeneic than after syngeneic marrow transplantation.

To determine whether allogeneic bone marrow transplantation (BMT) is associated with a graft vs leukemia (GVL) effect in man, the relapse rate of acute leukemia after allogeneic BMT was compared with that occurring after syngeneic (genetically identical twin) BMT. The patients had ALL or ANL in second or subsequent complete remission (CR) or in relapse. The allogeneic and syngeneic marrow recipients were comparable in diagnosis, age, and interval from diagnosis to BMT and received comparable chemoradiotherapy regimens. Allogeneic marrow recipients, however, received, in addition, GVH disease prophylaxis, most often methotrexate and, more recently, cyclosporine or both. All patients treated by the Seattle team from 1970-1986 are included. Leukemic recurrence was observed in 62% of 785 allogeneic recipients and 75% of 53 syngeneic recipients (p less than 0.0001). The results confirm the circumstantial evidence for a GVL effect exerted by allogeneic marrow. Analyses are in progress to determine whether a GVL effect exists in subsets of patients as a function of their particular diagnosis or status at the time of BMT.

Bone Marrow Transplantation↗
PubMed1987

Treatment of marrow graft recipients with thymopentin.

Four adult patients with acute non-lymphocytic leukemia were given marrow grafts from HLA-identical siblings following 120 mg/kg cyclophosphamide and 10-12 Gy total body irradiation. All received intermittent intravenous methotrexate as prophylaxis against graft-versus-disease (GVHD). In an attempt to accelerate immune recovery and prevent GVHD, each patient received thymopentin (TP5) for 100 days after grafting. No adverse effects were seen with TP5 administration. All four patients developed acute GVHD (one grade I, one grade II, and two grade III). Two patients died of late infections: one at 6 months from Pneumocystis carinii pneumonia and one at 11 months from disseminate Pseudomonas, Candida and cytomegalovirus infection. Two patients survive more than 3.9 years after transplantation with Karnofsky scores of 100%. One required treatment for chronic GVHD and recovered. Delayed-type hypersensitivity, antibody production to specific antigen in vivo, and results of in vitro immunologic studies were not altered by TP5 treatment. We conclude that while the administration of TP5 in these patients as described was not harmful, it did not prevent opportunistic infection, improve immunologic reconstitution or lower the incidences of acute or chronic GVHD from that of our previous experiences without thymopentin.

Adult↗
PubMed1987

Treatment of aplastic anemia with antithymocyte globulin, high-dose corticosteroids, and androgens.

A total of 46 patients with aplastic anemia (34 severe; 12 moderate) were treated with antihuman thymocyte globulin (ATG), high-dose methylprednisolone, and oxymetholone. Early symptoms of ATG toxicity included fever, rash, and bronchospasm. Signs of serum sickness also developed in 23 patients. Complications associated with high doses of steroids were hyperglycemia, hypertension, fluid retention, gastrointestinal hemorrhage, and aseptic necrosis of the hip. Other morbidity possible associated with steroid administration included seizures, arrhythmias, and headache with papilledema. Studies of elevated liver function necessitated discontinuation of androgen therapy in eight patients. A complete or partial hematological response was noted in 19 patients (41%). Of these, three have had recurrent cytopenias, of whom one has developed a myelodysplastic syndrome. There are currently 34 patients surviving, and 12 who have died. Actuarial survival at three years is 65%. These response and survival data are comparable to those of previous trials using ATG and androgens without high-dose steroids. A prospective, randomized trial is needed to determine whether the addition of high-dose corticosteroids to ATG does significantly increase the rate and frequency of response in order to justify the toxicity of this additional immunosuppressive therapy in the treatment of aplastic anemia.

Adult↗
PubMed1987

Direct ultrastructural evidence of target-directed polarization by cytotoxic lymphocytes in lesions of human graft-vs-host disease.

Cytotoxic lymphocytes are thought to kill target cells by means of potent cytotoxic granules that congregate near the microtubular organizing center and the Golgi apparatus at one pole of the killer cell. We searched for evidence of this type of polarization in 12 lip biopsy specimens from patients with acute and/or chronic graft-vs-host disease (GVHD) compared with two lip specimens from normal individuals. Lymphocytes with such polarization were found in contact with epithelial cells of the squamous mucosa in all 12 cases of GVHD, and cells of the cuboidal minor salivary duct epithelium were found in two of 11 evaluable cases. The data add support to the hypothesis that cytolytic lymphocytes attack epithelial cells in GVHD.

Adolescent↗
PubMed1986

A dominant influence of flanking sequences on a local structural transition in DNA.

We have discovered a striking dependence of a structural transition in DNA on sequences that are distanced from those directly participating in the transformation. The dominant factor determining the selection of kinetic properties of cruciform extrusion is the sequence of the DNA that flanks the inverted repeat. The sequence of the inverted repeat itself appears to have little or no influence. The critical sequences that confer the unusual kinetics exhibited by the ColE1 cruciform are very A+T-rich. A single such sequence is sufficient, which may be as short as 100 bp, and it can control inverted repeats placed at either end. The effects operate in cis, are independent of polarity, and may be effective over relatively long distances. The influence of context has wide implications, possibly including the control of gene expression.

Bacteriocin Plasmids↗
PubMed1986

The structure of cruciforms in supercoiled DNA: probing the single-stranded character of nucleotide bases with bisulphite.

The single-stranded character of cytosine bases in three cruciform structures has been assessed by an examination of reactivity towards sodium bisulphite. Unpaired cytosine residues undergo deamination at C4 to give deoxyuracil, and propagation in an ung Escherichia coli host results in C-G----T-A transition mutations, detectable by restriction cleavage or sequence analysis. Very high frequencies of such mutations have been found at cruciform loops, confirming their unpaired character, with almost zero background mutation frequencies elsewhere. A low level of modification was observed at the four-way junction of a cruciform. The results indicate that the optimal cruciform loop size is four bases, with loose 'breathing' at the first base pair at the top of the cruciform stem at 37 degrees C, and little or no opening of base pairs at the four-way junction.

Base Sequence↗
PubMed1986

Selection of patients with Hodgkin's disease and non-Hodgkin's lymphoma for bone marrow transplantation.

Despite substantial progress in curative therapy of malignant lymphomas, some patients fail current treatment and die of refractory disease. Although Although high-dose chemotherapy and supralethal total body irradiation followed by bone marrow transplantation may salvage and cure a proportion of these refractory patients, treatment of such end-stage patients with marrow grafting often fails because of resistant disease or transplant-related complications. Using the analogy of transplantation in the early phases of acute and chronic leukemias, results of marrow transplant in Hodgkin's disease and non-Hodgkin's lymphoma might be improved if performed earlier in the course of the malignancy. The following collaborative report by the Seattle and Stanford groups examines current results of conventional lymphoma therapy to define subgroups of patients with "high-risk" lymphoma for whom early marrow transplant might be offered to control otherwise incurable disease.

Antibodies, Monoclonal↗